Eurotech Appliances ZEUS PXA270 - Manual (Page 40)

ZEUS Technical Manual Detailed hardware description
© 2007 Eurotech Ltd Issue D 40
CompactFlash
A CompactFlash extension socket for full I/O mode operation is provided by slot 0 of
the PXA270 PC card controller, and supports type I,II CF+ cards. It appears in PC card
memory space socket 0.
Address Region name
0x20000000 – 0x23FFFFFF Socket 0 I/O Space.
0x24000000 – 0x27FFFFFF Reserved.
0x28000000 – 0x2BFFFFFF Socket 0 Attribute Memory Space.
0x2C000000 – 0x2FFFFFFF Socket 0 Common Memory Space.
This is a hot swappable 3.3V interface, controlled by the detection of a falling edge on
GPIO35 of PXA270 when a CompactFlash card has been inserted (CF_CD#). On
detection, set GPIO97 (CF_PWEN) to logic ‘1’ to enable the 3.3V supply to the
CompactFlash connector. The CompactFlash RDY/BSY# signal interrupts on PXA270’s
GPIO99.
Many CF+ cards require a reset once they have been inserted. To reset the
CompactFlash socket independently set the CF_RST bit to ‘1’ in the REG2 register
located at the address 0x13000000. To clear the CompactFlash reset write ‘0’ to the
CF_RST bit.
CF reset register [REG2]
Byte lane Most significant byte Least significant byte
Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Field - - - - - - - - - - - - - - - CF_RST
Reset X X X X X X X X X X X X X X X 0
R/W - - - - - - - - - - - - - - - R/W
Address 0x13000000
CF+ is a small form factor card standard. It encompasses CompactFlash (CF) Flash
data storage cards, magnetic disk cards and I/O cards including serial cards, Ethernet
cards, fax/modem cards, digital phone cards, USB, barcode scanners, Bluetooth,
IEEE802.11b (WiFi), wireless digital cell phone cards, and so on. For more details about
CF+ standards and the availability of particular CF+ peripherals, see
www.compactflash.org .
The CF+ card provides high capacity data storage and I/O functions that electrically
comply with the Personal Computer Memory Card International Association (PCMCIA)
standard.
For connection details for the standard 50 pin CompactFlash connector, see
J20 –
CompactFlash connector , page 89 .